SaVi satellite constellation visualizer savi-dev

Adding support for graticule (lat/long lines).
Will be useful when no map is available,
showing coverage in Geomview.

Have not attempted cylindrical at this point,
so unprojected and unprojected mask only.

Improving packaging notes.

Packaging is a textfile, tellin svn it is with
svn propset svn:mime-type text/plain PACKAGING
svn ci

Making clear that it's axial tilt to orbit,
not orbital tilt to ecliptic plane.

fixing another edge case if coverage window is closed
while you select Mars.

Fixing first-time selection of colors, so we
pick the right planetary shades. Noticeable if
you select Mars in Simulations constants _before_
opening the Coverage window.

Adding Mars stationary constellation - separate script
from Clarke, so we can add explanation and references.

Noting Mars constellation menu is for Mars.

Setting per-planet default color shades.

So far, there is only Earth (default yellow to red and blue)
and Mars (whitish to gray, and red).

SaVi color shades in the menu now sets depending on what
the planet is.

Need to indicate in windows (main/coverage/fisheye)
what planet is being simulated.

Supporting changing menus between different bodies,
so that we can offer different simulations for each
planet/moon. (The Clarke stationary script will see
reuse, but its comments would need tweaking, at least.)

Constellations menu is used in main/coverage/fisheye.
Locations menu is just used in fisheye.